In a non-self-light-emitting display device, such as a liquid crystal display device, typically a backlight unit provides light for the display device. In an edge-lit backlight unit, light-emitting diodes (LEDs) are often used as a backlight source, i.e., an edge-lit backlight source emitting backlight. Through a light guide plate, the direction of the backlight incident onto a display panel may be changed, and thus the edge-lit backlight source may become a back-lit backlight source facing the display panel. The light emitted from the backlight source transmits through the display panel via an optical film, realizing image display functionality of the display device.
In a backlight unit, LEDs emitting white light are generally used. A plurality of LEDs are connected in series or in parallel, and a stable current is provided to each LED by a respective control unit. In this way, the LEDs may remain in stable brightness, maintaining normal display of various images.
However, due to the difference between images displayed on display panel, the needs of the display panel for various colors of light may change over time. Especially when a display panel displays a monochrome image, pixels that are irrelevant to the color of the displayed image are closed or turned off. However, at this time, the backlight source still provides light to the pixels that are closed, resulting a loss of backlight energy. Therefore, a reasonable allocation of the energy of a backlight source, and further reduction of power consumption of a backlight source, are problems that are need to be urgently addressed in the field of display technologies.
The disclosed methods and structures are directed to solve one or more problems set forth above and other problems in the art.